:root{--ink:#101712;--muted:#667168;--line:#d8e2db;--paper:#fff;--soft:#f5f8f4;--green:#1f7a52;--green-dark:#155a3d;--gold:#b7772a;--shadow:0 22px 60px rgba(16,23,18,.09)}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--soft);color:var(--ink);font-family:Inter,-apple-system,BlinkMacSystemFont,"Segoe UI",Arial,sans-serif;line-height:1.55}
button,input,select{font:inherit}
a{color:inherit}
.wrap{width:min(1120px,calc(100% - 40px));margin:auto}
.topbar{min-height:72px;display:flex;align-items:center;justify-content:space-between;gap:20px;padding:14px max(20px,calc((100vw - 1120px)/2));background:rgba(245,248,244,.97);border-bottom:1px solid var(--line);position:sticky;top:0;z-index:20}
.brand{display:flex;align-items:center;gap:9px;text-decoration:none;font-size:20px;font-weight:900;letter-spacing:-.055em}
.brand span{color:var(--green)}
.tagline{color:var(--muted);font-size:11px;font-weight:750;letter-spacing:.08em;text-transform:uppercase}
.nav-actions{display:flex;align-items:center;gap:13px}
.tools{position:relative}
.tools>button{border:1px solid var(--line);background:#fff;color:var(--ink);border-radius:9px;padding:10px 13px;font-weight:800;cursor:pointer}
.tools>button span{color:var(--green)}
.tools-panel{position:absolute;right:0;top:calc(100% + 9px);width:295px;padding:9px;background:#fff;border:1px solid var(--line);border-radius:14px;box-shadow:var(--shadow)}
.tools-panel[hidden]{display:none}
.tools-label{padding:8px 10px 6px;color:var(--muted);font-size:10px;letter-spacing:.12em;text-transform:uppercase;font-weight:850}
.tool{display:flex;gap:10px;align-items:flex-start;padding:11px 10px;border-radius:9px;text-decoration:none}
.tool:hover{background:#f1f6f2}
.tool strong{display:block;font-size:13px}
.tool small{display:block;color:var(--muted);font-size:11px;margin-top:2px}
.tool-icon{width:25px;height:25px;display:grid;place-items:center;border-radius:7px;background:#edf7f1;color:var(--green-dark);font-weight:900;flex:none}
.home-link{color:var(--green-dark);font-size:13px;font-weight:850;text-decoration:none}
.intro{padding:74px 0 42px;background:linear-gradient(135deg,#eef6f0 0%,#f8faf7 60%,#f6f1e8 100%);border-bottom:1px solid var(--line)}
.eyebrow{color:var(--green-dark);font-size:11px;font-weight:900;letter-spacing:.14em;text-transform:uppercase}
h1,h2{font-family:Georgia,"Times New Roman",serif;font-weight:500;letter-spacing:-.06em}
h1{max-width:760px;margin:14px 0 16px;font-size:clamp(48px,7vw,82px);line-height:.98}
.lead{max-width:690px;margin:0;color:#405046;font-size:20px;line-height:1.5}
.tool-section{padding:30px 0 72px}
.calculator{background:#fff;border:1px solid #cbdacf;border-radius:18px;box-shadow:var(--shadow);overflow:hidden}
.mode-tabs{display:flex;gap:4px;padding:10px;background:#f1f5f1;border-bottom:1px solid var(--line)}
.mode-tab{flex:1;border:0;border-radius:10px;background:transparent;color:var(--muted);padding:13px 12px;font-size:13px;font-weight:850;cursor:pointer}
.mode-tab:hover{color:var(--ink)}
.mode-tab.active{background:var(--green-dark);color:#fff;box-shadow:0 7px 16px rgba(21,90,61,.16)}
.mode-panel{padding:32px}
.mode-panel.is-hidden{display:none}
.panel-heading{display:flex;justify-content:space-between;gap:30px;align-items:flex-start;margin-bottom:26px}
.panel-heading>div{display:flex;gap:14px;align-items:flex-start}
.panel-number{color:var(--green);font-size:11px;font-weight:900;letter-spacing:.12em;padding-top:7px}
.panel-heading h2{margin:0;font-size:31px;line-height:1.04}
.panel-heading p{max-width:425px;margin:1px 0 0;color:var(--muted);font-size:13px}
.form-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:17px}
label{display:grid;gap:7px;color:#344238;font-size:12px;font-weight:800}
input,select{width:100%;border:1px solid #cbd8ce;border-radius:9px;background:#fff;color:var(--ink);padding:12px 12px;outline:none}
input:focus,select:focus{border-color:var(--green);box-shadow:0 0 0 3px rgba(31,122,82,.12)}
.input-with-unit{display:flex;min-width:0}
.input-with-unit input{min-width:0;border-radius:9px 0 0 9px}
.input-with-unit select,.input-with-unit span{display:flex;align-items:center;justify-content:center;min-width:83px;border:1px solid #cbd8ce;border-left:0;border-radius:0 9px 9px 0;background:#f5f8f4;color:var(--muted);font-size:12px;padding:0 9px}
.input-with-unit select{cursor:pointer}
.is-hidden{display:none!important}
.calculate{display:inline-flex;align-items:center;gap:16px;margin-top:28px;border:1px solid var(--green-dark);border-radius:10px;background:var(--green-dark);color:#fff;padding:13px 17px;font-size:13px;font-weight:850;cursor:pointer;box-shadow:0 9px 20px rgba(21,90,61,.15)}
.calculate span{font-size:18px;line-height:0}
.calculate:hover{background:#0f4b32}
.result{margin-top:24px;border-top:1px solid var(--line);padding-top:24px}
.result-empty{color:var(--muted);font-size:13px}
.result-card{display:grid;grid-template-columns:minmax(0,1fr) 1.25fr;gap:25px;align-items:center}
.result-main{padding:18px 21px;background:#edf7f1;border:1px solid #c9e2d2;border-radius:13px}
.result-label{color:var(--green-dark);font-size:11px;font-weight:900;letter-spacing:.1em;text-transform:uppercase}
.result-value{margin-top:7px;font-size:clamp(28px,4vw,45px);line-height:1;letter-spacing:-.06em;font-weight:900}
.result-sub{margin-top:8px;color:var(--muted);font-size:12px}
.result-details{display:grid;grid-template-columns:1fr 1fr;gap:10px}
.detail{padding:13px 14px;border:1px solid var(--line);border-radius:10px}
.detail span{display:block;color:var(--muted);font-size:11px}
.detail strong{display:block;margin-top:3px;font-size:15px}
.result-note{grid-column:1/-1;margin:0;padding:12px 14px;border-left:3px solid var(--gold);background:#fbf6ed;color:#68502e;font-size:12px}
.safety{margin:18px auto 0;max-width:940px;padding:14px 17px;border:1px solid #e7d6b6;border-radius:11px;background:#fffaf1;color:#6d542d;font-size:12px}
.explain{padding:72px 0;background:#101712;color:#fff}
.explain-grid{display:grid;grid-template-columns:.9fr 1.1fr;gap:70px}
.explain h2{max-width:450px;margin:11px 0 0;font-size:clamp(32px,4vw,48px);line-height:1.03}
.explain .eyebrow{color:#8fd0aa}
.copy{max-width:550px;color:#b9c7bd;font-size:15px}
.copy p{margin:0 0 16px}
.faq{padding:70px 0}
.faq-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:13px;margin-top:20px}
details{background:#fff;border:1px solid var(--line);border-radius:12px;padding:17px}
summary{cursor:pointer;font-weight:850;font-size:14px}
details p{margin:12px 0 0;color:var(--muted);font-size:13px}
.footer{padding:25px 0;border-top:1px solid var(--line);color:var(--muted);font-size:11px}
.footer-inner{display:flex;justify-content:space-between;gap:18px}
.footer a{color:var(--green-dark);font-weight:800;text-decoration:none}
@media(max-width:850px){.tagline{display:none}.panel-heading{display:block}.panel-heading p{margin:13px 0 0}.form-grid{grid-template-columns:repeat(2,1fr)}.result-card{grid-template-columns:1fr}.explain-grid{grid-template-columns:1fr;gap:25px}.faq-grid{grid-template-columns:1fr}}
@media(max-width:570px){.wrap{width:min(100% - 28px,1120px)}.topbar{padding:12px 14px}.home-link{display:none}.intro{padding:52px 0 34px}.lead{font-size:17px}.mode-tabs{display:grid;grid-template-columns:1fr}.mode-panel{padding:22px 18px}.panel-heading h2{font-size:27px}.form-grid{grid-template-columns:1fr}.calculate{width:100%;justify-content:space-between}.result-details{grid-template-columns:1fr}.footer-inner{display:grid;gap:6px}}